General Motors reported that it sold just shy of 2.6 million vehicles in 2012, beating its 2011 total volume by 3.7 percent. The automaker finished the year by posting a December 2012 sales gain of 4.9 percent, pushing the automaker to its strongest December sales tally since 2007.

GM also noted that it sold one million vehicles that are EPA rated for at least 30 mpg highway. That's due in part to the fact that 40 percent of the company's cars had four-cylinder engines last year -- up from just 30 percent in 2011.The company's two pickups, the Sierra and Silverado, continued to sell well as GM pumped out as many copies as possible of the current generation. Brand new versions of the trucks debuted late last year for the 2014 model year. Unfortunately, cranking up production created a huge backlog of vehicles that will likely be sold with massive inventories. As of December 31, GM has 221,648 unsold pickup trucks, or an 80-day supply.

Loser: Buick -- 16,473 sales, up 10.0 percentDespite a strong finish to the year -- overall Buick saw its sales climb just 1.6 percent last year -- the brand is still smarting from the loss of the strong-selling Lucerne. In fact, every single nameplate saw its total 2012 sales fall compared to 2011. Nonetheless, the Enclave crossover brought in plenty of buyers, with sales up 8.9 percent to 6052 last month, even as total annual sales fell 2.9 percent. LaCrosse sales dropped 24.0 percent to 4074 units and ended the year down 2.4 percent, the Regal suffered a 50.6-percent drop to 1526 monthly sales and ended 2012 down 38.7-percent year-over-year.

A good result in December can't hide the grim news for Cadillac. The brand posted GM's worst annual result, with sales dropping 1.7 percent versus 2011.Losing the DTS and STS, long the brand's best sellers, really hurt Cadillac sales, and the new ATS and XTS sedans have yet to sell strongly enough to make up for that loss. The 2013 ATS, for its part, sold 2979 units last month for a total of 7008 cars in 2012, while the XTS sold 2939 cars in December and a total of 15,049 last year.Elsewhere, Cadillac posted mostly negative numbers. CTS coupe, sedan, and wagon sales fell 37.8 percent in December to 3372, and overall last year the model's sales were 14.6-percent off the pace set in 2011. Escalade sales of 2554 units represented a 22-percent drop last month, and for the entire year the luxury SUV saw its sales volume slip 11 percent. The SRX crossover was the only bright spot, as although its December sales fell 12.6 percent to 6400 units, overall the car recorded a 1.0-percent sales gain in 2012.Winner: Chevrolet -- 167,091 sales, up 3.7 percentChevrolet posted the biggest sales gains of any GM brand last year, with total volume up 4.3 percent year-over-year. Several models made enormous leaps in sales volume: the Sonic compact, for instance, finished December up just 4.3 percent, but a strong year helped push the car to a 415-percent overall gain compared to its first year on sale. The Chevrolet Volt, too, saw sales leap 206 percent from just 7671 units in its difficult first year on the market to a respectable 23,461 cars in 2012.Despite a significant drop to just 1293 sales last month, the Colorado small pickup posted an 18.7 percent annual sales gain. And the Equinox crossover enjoyed a 7.5-percent boost to 19,551 December sales and ended the year up 13.1 percent.

The Silverado pickup truck was, once again, Chevrolet's top seller with annual volume flat at 418,312 units, with the Cruze sedan closely following at 237,758 units -- a gain of 2.6 percent versus last year. Third place went to the aforementioned Equinox, while the Malibu sedan came in fourth with a total of 210,951 sales, representing a modest 3.0-percent year-over-year gain.There were, of course, some surprises. News of its imminent demise appears to have jumpstarted Avalanche sales; the truck finished December up 7.5 percent and ended 2012 up 19.4 percent. Sales of the Camaro sports car fell 13.6 percent last month to 5837 units and 4.4 percent for the year overall; however, the Camaro still managed to best its Ford Mustang rival by just 1396 units for all of 2012. Corvette sales, meanwhile, posted a 24.4-percent gain in December and finished 2012 up 7.4 percent, most likely as hardcore fans snapped up the remaining examples of the current C6 generation car. (An all-new Chevrolet Corvette arrives in less than two weeks' time at the Detroit auto show.)Mixed: GMC -- 43,291 sales, up 4.7 percentWith four percent more vehicles sold in 2012 than a year prior, GMC enjoyed a year of strong sales. Its Sierra pickups finished December up 13.4 percent to 18,710 sales, and enjoyed a 5.4-percent gain for the entire year. The second-place model in terms of volume was the Terrain crossover, with December sales of 11,516 representing a gain of 49.1-percent year-over-year and helping push the nameplate to a 17.6-percent annual sales increase. The GMC Acadia saw its sales slip 29.6 percent last month to 5179 and overall for the year it dropped 1.3 percent. The Yukon SUV also struggled, with overall sales last year down 14 percent.Source: GM

I think there may be a period of adjustment for Buick and Cadillac, considering that they are both creating a different image and trying to be more appealing to a younger market. Those who used to enjoy the boats that Buick and Cadillac excelled in are either gone, or moved on to another type of boat. An ATS or a Regal GS just will not be appealing to the silver haired customer of old, in most cases. If they can develop their names and change opinions, however, they can attract the customer they are looking for. Since both have shown dramatic improvement, I hope that the consumer who was previously looking for a Japanese or German luxury auto will give them a shot.

I question the statement about Buick, where the article indicates every single model decreased sales year over year. Buick has this new model named Verano maybe you've heard of it - that, according to GM's website, was Buick's secondbest selling model in December, behind the Enclave and sold double (over 40K) what the Lucerne sold last year.

After the new silverado and new corvette come out im sure this will be and even better year for GM. However i think that the cruze is starting to feel a little bit dated and could probably use a 2014 refresh or even a whole new model for 2015, same goes for the equinox IMO.

I'm surprised that the Buick Regal doesn't sell that well. It's a terrific competitor to the Acura TSX, and there is definitely a market for a small, premium midsize. Very much like the Suzuki Kizashi...